What are the uses of damper winding in a synchronous motor?

Detailed Solution. The damper winding in synchronous motor performs two functions: Prevents hunting (damped out oscillations) Provides starting torque (made self-starting)

Why is damper winding used in a synchronous motor stator?

The main purpose of using Damper winding in synchronous Machine is to provide starting torque and eliminate damping or hunting. The damper winding is used in Synchronous Motor to provide starting torque and the damper winding is used in the synchronous alternator to eliminate damping or hunting.

Where is damper winding in synchronous motor?

Damper winding in synchronous machine is placed in the coil slots and short circuited. Thus Damper winding provides the same effect as the squirrel cage winding rotor does in case of induction motor.

What controls the speed of a synchronous motor?

Speed of synchronous motors can be controlled using two methods called open loop and close loop control. Open loop contol is the simplest scalar control method where motor speed is controlled by independent frequency control of the converter.

Where damper winding is used?

Functions of Damper Windings: Damper windings helps the synchronous motor to start on its own (self starting machine) by providing starting torque. By providing damper windings in the rotor of synchronous motor “Hunting of machine”can be suppressed.

What is damping in synchronous motor?

Definition of damper winding : a short-circuited squirrel-cage winding placed in the pole faces and around the pole shoes of synchronous machines, the currents induced in the winding by the periodic variations in synchronous speed having the effect of a damper. — called also amortisseur.

What is a damper winding on a motor?

What is damper winding?

How do you control synchronous speed?

We can achieve the speed control of synchronous motor either by changing the number of Stator poles or changing the frequency of AC supply. Varying the frequency is a feasible way for speed control of the synchronous motor. Using the rectifier and inverter combination, we can vary the frequency of AC supply.

How does damper winding of a synchronous motor reduce hunting?

Reduction of Hunting in Synchronous Motor Use of Damper Winding: It consists of low electrical resistance copper / aluminum brush embedded in slots of pole faces in salient pole machine. Damper winding damps out hunting by producing torque opposite to slip of rotor.

What do you mean by damper winding?

Definition of damper winding : a short-circuited squirrel-cage winding placed in the pole faces and around the pole shoes of synchronous machines, the currents induced in the winding by the periodic variations in synchronous speed having the effect of a damper.

What is damping in synchronous machine?

Synchronous motors have their pole-shoes slotted for placing copper bars. The copper bars are placed in these slots and short-circuited at both ends by heavy copper rings (like squirrel cage rotor of induction motors). This arrangement is known as damper winding in synchronous motor.

Does damper winding carry current in synchronous motor?

Thus, under normal running conditions, damper winding in synchronous machine does not carry any current. The stator and the rotor poles of running synchronous motor are magnetically locked and, hence, both run with the same synchronous speed. But centerlines of the two poles do not coincide with each other.

What is the induced emf in the damper winding of synchronous motor?

This arrangement is known as damper winding in synchronous motor. When the rotor is rotating at synchronous speed, then the relative velocity between the RMF (rotating magnetic field of the stator) and the rotor is zero. Hence induced EMF in the damper winding is zero.

Is a synchronous motor a self starting machine?

Synchronous motors are not self starting machines. These machines are made self starting by providing a special winding in the rotor poles, known as damper winding or squirrel cage windings. The damper winding consists of short circuited copper bars embedded in the the face of the rotor poles

What is the difference between induction motor and synchronous motor?

Due to the damper winding present in the rotor winding of the synchronous motor, machine starts as induction motor (Induction machine works on the principle of induction. Damper windings in synchronous motor will carryout the same task of induction motor rotor windings.